atournas Posted September 26, 2011 Share #1 Posted September 26, 2011 Advertisement (gone after registration) Hi, I wonder if people regularly rate Ektar ISO 100 minus 1/3 stop. Are the results any better? Thanks Paul Link to post Share on other sites More sharing options...
Advertisement Posted September 26, 2011 Posted September 26, 2011 Hi atournas, Take a look here Ektar 100 rated 80. I'm sure you'll find what you were looking for!
Carl E Posted September 26, 2011 Share #2 Posted September 26, 2011 I expose normally (100 ISO) as I would think that +/- 1/3 step is well within the (considerable) exposure latitude of colour negative film, but then I suppose it depends on your shooting style and how accurately you go about measuring the luminance of your subject. Link to post Share on other sites More sharing options...
useless generation Posted September 26, 2011 Share #3 Posted September 26, 2011 I always rate it at 80 and get good results! All the color work on my blog was shot on ektar at 80 photographic nostalgia Link to post Share on other sites More sharing options...
Guest sterlinstarlin Posted September 26, 2011 Share #4 Posted September 26, 2011 I always rate it at 80. Link to post Share on other sites More sharing options...
Michael Geschlecht Posted September 27, 2011 Share #5 Posted September 27, 2011 Hello Everybody, When I use film - Transparency or Negative - I always read the DX code printed on the cartridge w/ a DX code reader I xerox'd from the pages of Modern Photograpy back in June of 1983. The interesting thing about reading DX codes - Just like an M7 does, which might be why some prefer the meter in the M7 to that in the MP - is you see that only some films are actually the speed they say on the box. Most transparency films are what they say they are. Some like Kodachrome had little latitude - DX codes on a cartridge tell you a film's speed, latitude & how many exposures are on that individual roll. Most negative films are really 1 stop slower than they are marked but have a greater acceptable exposure range than transparency films in general. For example: Most negative films have a speed on the box that was chosen so you could over expose it 3 stops or under expose it 1 stop & still have a good print. Optimal exposure would be + or - 2 stops (1/2 the ISO on the box). Most transparency films are + or - 1 stop except Kodachrome which was + or - 1/2. When I have used Ektar in the past - I haven't used it for a while - unlike most print films its latitude was + or - 1 stop, the speed marked on the box, like Ektachrome which is a transparency film. Not the -1/3 some seem to prefer today. There is a setting for that on the reader. It's possible the actual film speed has been changed. Various manufacturers have done so in the past. I would have put this DX code reader w/ diagrams & explanations on the Forum long ago but I don't know much about using computers & I don't know how to. If anyone would like they could show me a picture of the black & white patches on the cartridge & tell me which side the spool comes out on. I would be glad IN THIS THREAD to tell them the ISO on the box (Not the name or brand), the actual film speed & exposure range. Also the # of exposures in that cartridge. I cannot always tell you whether it is a transparency or negative film because some, like Ektar & Ektachrome 100 read exactly the same. Best Regards, Michael Link to post Share on other sites More sharing options...
atournas Posted September 27, 2011 Author Share #6 Posted September 27, 2011 Michael, that's interesting info, but I'm a little confused. Are you saying DX coding is the REAL rating, usually different than what the film box says? Paul Link to post Share on other sites More sharing options...
prunelle Posted September 27, 2011 Share #7 Posted September 27, 2011 Advertisement (gone after registration) Hello Everybody, When I use film - Transparency or Negative - I always read the DX code printed on the cartridge w/ a DX code reader I xerox'd from the pages of Modern Photograpy back in June of 1983. The interesting thing about reading DX codes - Just like an M7 does, ... Hi Michael, Nice to see you here! What you say is highly interesting and I'd like to know more. Do your diagrams look -even vaguely- like that: DX encoding - Wikipedia, the free encyclopedia? I understand how to use the diagrams on the wikipedia page but, if the ISO in the DX encoding is different from the ISO mentioned on the box, which one should I consider? The one in the DX code or the one on the box? And Michael, you're a gold mine. Link to post Share on other sites More sharing options...
Doc Henry Posted September 27, 2011 Share #8 Posted September 27, 2011 .... look at this link and you will see how iso works best for Ektar 100 : A Dark Topography: Ektar 100: The DarkTopo Film Test! usually i use for outdoor shooting 100 iso Best Henry Link to post Share on other sites More sharing options...
tgray Posted September 27, 2011 Share #9 Posted September 27, 2011 I've shot it at 80 before with no problems. And even at lower ratings. I sometimes prefer to shoot color neg 1/3 or 2/3rds of a stop over exposed relative to the box speed for two reasons. First is that it moves more of the exposure onto the slower fine grained parts of the emulsion, generally reducing grain. This works well on 400 and 800 speed films. Secondly, it let's me a be a bit sloppier with my metering - if I actually meter wrong and give a shot 1/3 or 2/3rds of a stop of underexposure, and I've already rated the film slower than box by 1/3 or 2/3rds of a stop, I'm back at box speed, ensuring shadows don't get that nasty. Think of it as a safety net. The second reason can still apply to Ektar. The first, not so much. It's already so fine grained that I don't think there is any real advantage to trying to reduce the grain. That being said, I think it looks best at box speed with proper metering and exposure. Since I'm usually a bit more careful with my metering and exposures with slow speed film, I usually just rate Ektar at box. Portra 400 and 800, on the other hand, are usually shot in more varying conditions, get downrated to 1/3 of a stop more often. Link to post Share on other sites More sharing options...
Stealth3kpl Posted September 27, 2011 Share #10 Posted September 27, 2011 .... look at this link and you will see how iso works best for Ektar 100 :A Dark Topography: Ektar 100: The DarkTopo Film Test! usually i use for outdoor shooting 100 iso Best Henry Thanks for this link. Slight thread hijack. I was having a look through the gallery here (Dec of Arms). In some of the photos a chap stands next to the shooter holding some sort of meter (?). I'm just wondering what it is for? http://www.darktopography.com/declarearms/gallery/images/declarearms19.jpg Pete Link to post Share on other sites More sharing options...
aesop Posted September 27, 2011 Share #11 Posted September 27, 2011 Michael, that's interesting info, but I'm a little confused. Are you saying DX coding is the REAL rating, usually different than what the film box says? Paul ...Michael, good to hear from you. Unlike Paul, I am not "a little confused". What is the value (to either the manufacturer or the end user) in marking a film canister with a speed different from that represented by the DX coding? If, as you appear to be suggesting, the DX coding is always correct, then it makes no sense to print a different speed on the canister or box. DX coding is no dark art, so I struggle to see any rationale in what you suggest. Link to post Share on other sites More sharing options...
earleygallery Posted September 27, 2011 Share #12 Posted September 27, 2011 Does anyone really see difference with 1/3 a stop ?!! Link to post Share on other sites More sharing options...
Eastgreenlander Posted September 27, 2011 Share #13 Posted September 27, 2011 Does anyone really see difference with 1/3 a stop ?!! I dont really see the point either. Aperture or shutter increments are not that small that it should matter in practical use. Or is it? --- I am here: http://maps.google.com/maps?ll=65.613505,-37.637208 Link to post Share on other sites More sharing options...
Michael Geschlecht Posted September 28, 2011 Share #14 Posted September 28, 2011 Hello Everybody, It is interesting that people are bringing up this series of very interesting & pertinenent questions. This is similar to the types of questions people asked in 1983 or so when DX coding began to be used in a big way. I think I might know the answers to some of these questions & comments but I want to do them in more than 1 Post so the size of a Post dosen't become cumbersome. I would also like to start from the top altho I would like to actually start w/ a comment about James's comment. There is a myth that knowledge, especially w/ the advent & development of computers, is an ever expanding inverted pyramid. Myth because while it is true there is more known today than there was before: The inverted pyramid alone is not an appropriate paradigm for the agglomeration of knowledge because it doesen't address the issue of knowledge which is lost. DX codes. To begin w/ James's comment: Actually 1/3d of a stop does matter. 1/3d of a stop was chosen as opposed to another number to be the unit for measuring exposure by DIN when they were determining film speeds. It was the closest convenient fraction of a stop which meant something: 1/3d of a stop is usually the MINIMUM exposure difference needed for the average person to see a definite change in density when examining silver based negatives. So yes, 1/3d of a stop makes a difference. Now to Anne: Yes, it's close enough so anyone would be equally happy w/ either. My diagrams have no "custom settings" section. 40 & 60 frames were just dashed lines altho @ the time my chart was printed (1983) 1 of those lines was used to indicate 27 exposure cartridges made by Agfa & perhaps some others. 72 was for estar based films. Thinner than the others. I think it might have been a special type of Tri-X designed w/ news photographers in mind. Leitz made a special counting disc for M's for this. It may or may not have required additional retrofitted gearing. When reading this chart the spool end of the cartridge is ALWAYS on the left side & the cartridge is ALWAYS held w/ both lines visible together. Reading from the LEFT the first space is ALWAYS Bright. Then, if this were the roll of Ektar in Henry's article from 2009 the top line, after the always B @ the left side, would read Dark, B, D, B, D. The lower line, after the always B @ the left side, would read B, B, D for 24 exposures or D, D, B if it were 36. Then followed by B, D for + or - 1 stop. Easy. Time for a new Post. Best Regards, Michael Link to post Share on other sites More sharing options...
Michael Geschlecht Posted September 28, 2011 Share #15 Posted September 28, 2011 Hello Again Everybody, To answer Anne, Aesop & Paul's question about why you may have 1 number on the box & another in the code is somewhat complex. The horsepower race does not only pertain to growing cabbages. It also sometimes takes place when assigning film speeds. If you define a film's speed as that point on the exposure scale where the best quality image is produced then any film only has 1 speed. But if you look @ some modern films, especially negative films you see something interesting. Some negative films have a wider range of points where you can assign a value & still get a good picture. For some people this situation has possibilities. If a company wants to make a film appear to be faster where there is still lots of room to expose on either side then: If they change the Exposure Index from where the best quality photo can be made to where the 1 stop safety factor is still there on the underexposure side that will give you an Exposure Index # which on paper is higher than the Exposure Index # for best exposure. Therefore w/ spool to our left, lower line: The last 2 places read B, B. Apparently a bigger or tastier cabbage. Altho in this case it is the same cabbage. Next scenario: Enter the electronic shutter. Capable of more accurate exposure TIMING. Now if a manufacturer wants to make the best of their accurate electronic shutter they better expose film @ that E.I. that produces the best, not just the good exposure. What to do? SLR lens makers solved an analagous problem of how to mechanically compensate for what the lens barrel says in the F stop display while the meter is metering the T stop aperture. F stops are not T stops but many people more or less think they are. Lens makers want to make people happy. So: They put a series of cams in a lens so when the lens is open a correction factor is registered to compensate for fall off. As the lens is stopped down this factor is adjusted. You lens says it is set @ 1.4 while the exposure metering system knows F1.4 is not T1.4 & compensates & adds some extra exposure. As you stop down the compensation is dialed away. Electronic shutter manufacturers wanted the better pictures they knew their more accurate shutters could produce. Film manufacturers put the little doo-dads on their cartrages & the camera makers added little gold plated pins, etc in their bodies. Many people think an M7 has a more accurate exposure meter than an MP altho I would guess if you turned off the DX reader & you manually entered the speed from the film box into the camera's non DX film speed setting mechanism it would produce the same exposure readings as the MP as long as they both measured the same thing using the same lens @ the same aperture. Best Regards, Michael Link to post Share on other sites More sharing options...
atournas Posted September 28, 2011 Author Share #16 Posted September 28, 2011 Michael, your last two posts appear so laborious that I can't argue without feeling some guilt. Well, one rational comment I read here is whether 1/3 stop will, in practice, make any noticeable difference. I suspect, with the roll processed professionally but not too meticulously, it won't be easy to tell. I see the 1/3 stop less ISO rate as a generic guideline of securing better color saturation. It's a textbook piece of advice, just like setting a slide film 1/3 stop faster (I always shoot Ektachrome 100 at 125). I just didn't have any experience with Ektar; I see now that the Ektar's 80 ISO is the rule rather than the exception. Thanks to everybody who responded Paul Link to post Share on other sites More sharing options...
tgray Posted September 28, 2011 Share #17 Posted September 28, 2011 Here's some more food for thought: Ektar 100 Test - a set on Flickr Ektar 100 exposed from 3 stops underexposed (EI 800) to 4 stops overexposed (EI 6) and then scanned and quickly adjusted for a decent picture. Sorry it's only in one stop increments. If you are reasonably careful with your metering, 100 should be fine. 80 should be too; I doubt you'll see any difference. If you are a bit sloppier with your metering or are shooting sunny-16, 80 (or even 64) is probably a good bet. Like a C-41 films, it's better to err on the side of overexposure than underexposure. Link to post Share on other sites More sharing options...
psamson Posted October 5, 2011 Share #18 Posted October 5, 2011 I consistently shoot Ektar 100 film at 80 and have solid results, with little need for post-processing. Example from a Hasselblad: https://picasaweb.google.com/lh/photo/cVBbMVE5Dlev-m0acYj1OA?feat=directlink Example from a M6: https://picasaweb.google.com/lh/photo/jLa-EBP7kNKlF7Ipk-z0Zw?feat=directlink However, I have spoken with some who noticed that Ektar may produce "mushy" results in overcast skies. Link to post Share on other sites More sharing options...
Guest srheker Posted October 5, 2011 Share #19 Posted October 5, 2011 I wonder if people regularly rate Ektar ISO 100 minus 1/3 stop. If you use a 100ASA film at 80ASA it is not minus 1/3 stop but plus 1/3 stop, meaning over-exposure instead of under-exposure! Many people used to underexpose their slide film by 1/3 stop (because in projection a slightly underexposed slide looks much better than a overexposed one, if you want prints that may be the other way round), but that would mean a setting of 125 ASA instead of 80! Link to post Share on other sites More sharing options...
Dan Ryan Posted October 6, 2011 Share #20 Posted October 6, 2011 Michael When I read what you said about photocopying something from a 1983 issue of Modern Photography to decipher DX coding, I took a chance and Googled the topic. What popped up was a page by Thom Hogan which explains the codes in graphic, easily understandable form. It is copied below in case it may be useful in addition to the wiki link provided by Anne. DX coding on film cassettes I immediately pulled out a roll of Velvia - sure enough, the codes told me that - 1 It is indeed 50 ISO 2 It has 36 exposures 3 The latitude of the film is + / - one half of a stop Then I examined a roll of Legacy Pro 400 - 1 It is confirmed as 400 ISO 2 It has 36 exposures 3 The latitude of the film is + 3 to - 1 stop 'Sunny 16' no longer seems so daunting. regards Dan Link to post Share on other sites More sharing options...
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